SO...WHAT IS IT??? -Identifying our unknown bacteria!

After a semester with our unknown bacteria, we have studied its physical characteristics, how it grows, how it moves, how it reacts in different conditions, and what it uses for energy. All the results of these tests have given us clues as to our mysterious unknown. Using the flow chart provided for us, we were able to FINALLY identify it!

These were the determining characteristics when using the flow chart:

• Gram positive--narrowing it down to Corynebacterium spp., Bacillus spp., and Lactobacillus spp.
• Spore-forming--narrowing it down to Bacillus spp.
• Positive mannitol test--narrowing it down to the species B. megaterium and B. subtilis
• Positive Voges-Proskauer (VP) test-- Bacillus subtilis!!!!

Now that we know what our bacteria is, we decided to do a little research on Bacillus subtilis. Here are some interesting facts that we found:

• naturally-occuring
• widespread
• used for its natural fungicidal properties to prevent crop disease
• Used in commercial Japanese and Korean food production
• Can convert explosives into nitrogen, carbon dioxide, and water
• Used as an immunostimulatory agent in alternative medicine

References:

• http://epa.gov/biotech_rule/pubs/fra/fra009.htm
• http://en.wikipedia.org/wiki/Bacillus_subtilis

Cow Antigens & ELISA Test

Testing the purity of bovine extract and albumin. The Petri dish is dived into three sections and we begin by making four holes in the agar for each section with a pipette.  Then we fill the holes with the substance indicated in the work sheet and checked the results next lab. In section one we added green dye in one hole, red dye in the second, Barium Chloride in the third and Potassium Sulfate in the fourth. The second section got Bovine Albumin to the first hole, Goat Anti-horse Albumin to the second, Goat Anti-bovine albumin to the third and Goat Anti-swine Albumin to the fourth. The third section got Goat Anti-horse Albumin, Goat Anti-bovine Albumin and Goat Anti-swine Albumin and Hamburger extract. Our results were a little confusing because the agar did not change colors like the other groups, but I don’t think there was any contamination that we could see.

Cow Antigen Results

The ELISA was to determine if Patient 3 and/or 7 have HIV.  We marked a plus sign on the wells to make a positive control sample, and used a negative sign on the wells for negative control samples, “3” wells for Patient 3’s results, and “7” wells for Patient 7’s results.  The results were that Patient 3 does not have an HIV infection, but Patient 7 does.

ELISA Results